Emergency Leak Detection

Trace and Access London

Trace and access sounds like one service and is really three. Finding the leak, opening up to reach it, and making the surface good again are different skills, different money and, crucially, different levels of urgency. Only the first one is an emergency.

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How trace and access work is priced

Job	How it is charged	Time
Stage one, locating the source	Fixed detection fee, agreed before travel	The urgent part
Stage two, opening up to reach the pipe	Quoted once the marked point shows what has to come up	Often better in daylight
Stage three, reinstating the surface	A separate trade and a separate quote	Days or weeks later
Attendance at night to stop the water	Out-of-hours band, named on the call	Immediately
Written record of the source and the access taken	Produced as part of stage one	After the survey

How each stage is charged, not a quote. The detection fee is fixed and agreed on the call, before an engineer travels.

Getting that clear is what stops a night call-out becoming an open-ended project. Once the supply is off and the source is marked, nothing is getting worse, and you have time to make the remaining decisions calmly rather than agreeing to them at 3am while standing in a wet hallway. Cutting and rebuilding are daylight work and cost less done that way.

Our engineers are on call through the night for the part that genuinely cannot wait: stopping the water and finding where it came from. What we will not do is open a floor on a hunch. Nothing gets cut until there is a marked point, because detection done properly is the only thing that keeps the opening small.

The three stages are priced as three, on purpose. The detection fee is fixed and agreed before anyone travels. Opening up is quoted once the marked point shows what actually has to come up, which is normally far less than a general estimate assumes. Reinstatement is a separate trade with its own quote, so you are free to use your own and can see plainly what each stage costs.

What you get

24/7 Rapid Response: We mobilise immediately, day or night, weekends and holidays.
Advanced Non-Invasive Detection: Using thermal imaging, acoustic sensors and moisture meters to locate leaks accurately.
Minimal Disruption Access: Precise, controlled opening of floors or walls only where needed.
London-Wide Coverage: From period homes in Islington to high-rises in Canary Wharf.
Immediate Leak Confirmation: We show you the evidence and explain the source on site.
Emergency Mitigation Advice: Guidance on immediate steps to limit damage while we work.

How it works

A method, not a guess

Stop the water

The stop tap first, talked through on the phone if need be. Everything else on this list is cheaper once the water has stopped moving.

Find the source, not the damp

The wet area and the fault are often in different rooms. The spread is followed back upstream until there is a point, not a region, to show you.

Open one place

The smallest opening that reaches the marked spot, agreed with you before anything is cut, and wherever possible done in daylight rather than overnight.

Hand over the making good

Plastering, tiling and flooring are a separate trade and a separate quote. Nothing is bundled in a way that stops you using your own contractor.

Before you book anyone

Three jobs, three prices: how to keep trace and access under control

Separate the three stages before you agree to anything

Finding the leak, opening up to reach it and making the surface good again are three different pieces of work, done by different skills, costing different amounts. Sold as one figure they become impossible to compare, to defer or to challenge. Ask for them itemised from the start. It is a reasonable request, it costs the firm nothing to comply with, and the reaction to being asked tells you a good deal about how the rest of the job will go.

Only the first stage is an emergency

Stopping the water and identifying where it came from cannot wait. Cutting into a floor and replastering a ceiling comfortably can. Once the supply is isolated and the source is marked, nothing is deteriorating, and every remaining decision is better taken in daylight by somebody who has slept. That split also moves the larger and more expensive part of the work out of the out-of-hours band, which is a saving available to anyone who understands the sequence.

Nothing should be opened before there is a marked point

This is the rule that decides whether you end up with one neat opening or a stripped room. Detection works entirely from the surface, so the search itself damages nothing. The moment cutting begins before the source is established, you are paying to explore, and exploration in a building with concealed pipework is expensive and open-ended. If a firm proposes opening up to have a look, you are being asked to fund guesswork.

The stain is where the water came out, not where it got in

Water runs along joists, spreads through screed and tracks pipework until something stops it, then appears at the lowest point it can reach. That can be a room away from the fault and a floor below it. A great many unnecessary holes exist because somebody opened the ceiling at the damp patch. Expect the engineer to work upstream from the visible damage rather than treating it as the destination, and be sceptical of anyone who does not.

Keep reinstatement visible and separately quoted

Plastering, tiling and flooring are a different trade from leak detection, and bundling them hides both. Quoted separately, you can compare it, postpone it, or hand it to your own decorator who will very likely do it better and for less. It also stops the making good being used to inflate a single opaque figure in which the part you actually needed, the finding, has quietly disappeared.

Have a reference point before the conversation starts

Negotiating at 3am without any sense of the market is difficult. Checkatrade publishes a UK average of £162 for leak detection, with most jobs between £115 and £234 and a full recorded spread of £80 to £1,600, and hourly diagnostic rates are published at £95 to £145. Those are third-party figures describing the trade rather than a quote for your building, and access and reinstatement sit outside them entirely. They are still enough to tell you when the detection element of what you are being quoted has drifted a long way from what the market does.

Compare like for like

Three jobs that get sold as one

Trace and access sounds like a single service and is really three: finding the leak, opening up to reach it, and putting the surface back afterwards. They are different skills, different money and, importantly, different levels of urgency. Only the first one is an emergency. Knowing where the lines fall between them is what stops a night call-out turning into an open-ended project.

What to check	A firm that quotes it as one job	A build-first contractor	How we run the call
How the work is described	One figure covering an undefined amount of finding, cutting and rebuilding.	Priced as construction, with the detection treated as a preliminary.	Three stages, named separately, so you can see which one you are approving at any point.
What has to happen tonight	All of it, ideally, while you are worried enough to agree.	Nothing until the schedule allows, which can be days.	Stop the water and find the source. Opening up and making good are daylight work and cost less done that way.
How much comes up	Whatever makes the pipe easy to reach, which is usually more than necessary.	Generous access, because reinstatement is the profitable half.	The smallest opening that reaches the marked point. Detection done properly is what keeps that opening small.
Who does the making good	Vaguely promised, frequently subcontracted, occasionally never arranged.	Their own team, bundled in whether or not you wanted it that way.	A separate trade and a separate quote, so you can use your own if you prefer. Nothing is bundled to obscure it.
Order of operations	Access begins before the source is confirmed, on the theory that it will turn up.	Programme-driven, so the cutting is booked before the finding is finished.	Nothing is opened until there is a marked point. Cutting first is how rooms get stripped for nothing.
Written record	An invoice listing a total and little else.	A works schedule, which describes the building work rather than the leak.	What was found, where it was, and what had to be opened to reach it, set down plainly.
Stopping the clock	The urgency is maintained, because urgency keeps the approvals coming.	Not their concern once the job is on the programme.	Once the supply is off and the source is marked, the emergency is over and you have time to make the rest of the decisions properly.

From the forums

The questions that come up when a leak starts

The trace and access discussions are written after the event, by people who have already had the leak fixed and are now looking at what it all cost. Read enough of them and the same structural complaint appears: nobody explained that this was three jobs rather than one.

Posts working backwards through a single bundled invoice

A common thread type is somebody trying to work out, after the fact, how much of a large total was finding the leak and how much was rebuilding the room. Usually it cannot be done, because it was never itemised. The advice that follows is always to require the three stages separated before agreeing to anything, and the people giving it are generally the ones who did not.

Accounts of rooms opened before the leak was located

These are the expensive stories. Floorboards up along a wall, ceilings down in two rooms, and the leak eventually found somewhere nobody had cut. What the writers identify in hindsight is the order of operations: access started before detection finished. The resulting consensus is that paying properly to locate is cheap compared with paying to explore, which is a conclusion reached by homeowners rather than by anyone selling detection.

Confusion about water appearing a room away from the fault

A steady stream of posts describe a stain in one room and a leak eventually traced somewhere quite different, with the intervening holes to show for it. The replies patiently explain that water travels along joists and through screed until something stops it. It is the single most useful physical fact in this whole subject and the one most often discovered the hard way, after the ceiling has already been opened at the damp patch.

Discussion about who should do the making good

Opinion runs consistently towards using your own decorator or tiler rather than accepting whatever is bundled, on the grounds of both cost and finish. Posters note that reinstatement is ordinary building work with no specialist element, and that firms which fold it into a single price rarely do it best. The recommendation is to take the detection and access from the specialist and put the finishing out separately.

Advice about photographing everything before it is touched

Repeated in nearly every thread and it costs nothing: photograph the damage, the source once found, and each stage of opening up, before anything is cleared or reinstated. People who did it describe every later conversation going more smoothly. People who did not describe trying to reconstruct events from memory after the room had been put back together.

Symptoms

When you need a trace & access report

Buildings insurance pays for finding hidden leaks and opening up, if the paperwork is right. Book a proper report when damage is insured.

Escape-of-water claim opened or about to be opened
Loss adjuster asking for cause and origin
Flat-to-flat leak dispute with the freeholder
Previous plumber visit without usable evidence
Need photos, moisture map and method statement

What insurers expect you to prepare

1Notify the insurer before instructing works where the policy requires it.
2Photograph damage and keep damaged materials if the adjuster asks.
3Collect policy schedule and claim reference.
4List any previous repairs or detection visits.

What “claim-ready” actually means

A one-line invoice is not enough. Adjusters want cause, origin, methods used, moisture readings and timestamped photos. Our reports are written for that desk, typically within 48 hours of the visit.

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London housing stock

Built for how London actually leaks

Housing stock across the capital fails in different ways. We match the method to the building, not a one-size survey script.

Victorian & Edwardian terraces

Original floorboards, cast-iron stacks and decades of patch repairs. We pressure-test circuits and listen through timber before any board is lifted.

Mansion blocks & conversions

Shared risers, stacked bathrooms and flat-to-flat disputes. Origin reports settle liability between leaseholders, freeholders and block insurers.

Post-war & 1970s stock

Copper branches, cold-water tanks and ageing joints. Acoustic and thermal methods locate slow drips that never show as a flood.

New-build flats & towers

Plastic pipe, underfloor heating and boosted mains. Tracer gas and thermal imaging matter more than a listening stick alone.

Questions

Trace & Access FAQs for London homeowners

What has to happen tonight and what can wait?

Stopping the water and finding the source are tonight. Opening up and making good are not. Once the supply is isolated and the fault is marked, nothing is deteriorating, and the cutting is better done in daylight by someone who can see properly. Splitting it that way also moves the larger part of the work into the cheaper daytime band.

How do you keep the damage to a minimum?

By not cutting until there is a point to cut over. Listening, imaging and pressure testing all work from the surface, so the search itself opens nothing. The opening is then sized to reach one marked spot. Rooms get stripped when access starts before detection has finished, which is the wrong way round and the most common reason these jobs escalate.

The ceiling is stained but the floor above is dry. What does that mean?

That water has travelled, which is entirely normal. It runs along joists, follows a screed layer or tracks a pipe until something stops it, then appears at the lowest point it can reach. The stain marks where it came out, not where it got in. Opening up at the stain is how people end up with two holes and a leak that is still running.

Do you do the replastering and tiling afterwards?

That is a separate trade and we quote it separately rather than folding it into one figure. Keeping it visible means you can compare it, defer it, or hand it to your own decorator. Bundling detection, access and reinstatement into a single number is how the finding part, which is the bit you actually needed, becomes impossible to price.

Should I open up myself to have a look first?

Please do not. Cutting into a wet ceiling risks bringing a lot of water down at once, and pulling boards near a live circuit is genuinely dangerous. It also destroys the evidence of where the water travelled, which is what the engineer follows back to the source. Shut the stop tap, put something under the drip, and leave the surfaces alone.

What is trace and access actually?

Three linked jobs. Tracing is locating the leak. Access is opening up whatever has to come up to reach it. The third, usually the largest, is putting the surface back afterwards. They involve different skills and different costs, and they are frequently sold as one number. Separating them is the first thing to do, because only the tracing part is genuinely urgent.

What has to be done tonight?

Stopping the water and finding the source. That is all. Once the supply is off and the fault is marked, nothing is getting worse and the remaining work is better and cheaper done in daylight. Splitting it that way also means the bigger part of the job is charged at the daytime band rather than the out-of-hours one.

How do you keep the damage down?

By not cutting anything until there is a point to cut over. Listening, imaging and pressure testing all work from the surface, so the search opens nothing at all. The access is then sized to reach one marked spot. Rooms get stripped when opening up begins before detection has finished, which is the wrong way round and the usual reason these jobs escalate.

There is a stain on my ceiling but the room above is dry. Why?

Because water travels. It runs along joists, follows a screed layer or tracks a pipe until something interrupts it, then emerges at the lowest point available. The stain marks the exit, not the entry, and the two can be a room apart. Opening up at the stain is the most common way of ending up with two holes and a leak that is still running.

Do you do the replastering afterwards?

That is a separate trade and we quote it separately rather than folding it into one figure. Keeping it visible lets you compare it, defer it or give it to your own decorator. Bundling detection, access and reinstatement into a single number is exactly how the finding, which is the part you needed, becomes impossible to price.

Should I open up the ceiling myself to look?

No. Cutting into a saturated ceiling can bring a great deal of water down at once, and pulling discussions near a live circuit is genuinely dangerous. It also destroys the evidence of how the water travelled, which is what the engineer follows back to the source. Shut the stop tap, contain the drip, photograph it and leave the surfaces alone.

Explore the cluster

Related leak detection services & guides

Leak detection London

Hub page for multi-method surveys

Acoustic detection

Listen for pressurised pipe noise

Thermal imaging

Map wet and warm anomalies

Tracer gas

Find plastic-pipe and screed leaks

Underground leaks

Supply pipe and mains traces

Pricing

Fixed fees and no find no fee

Areas we cover

All 33 London boroughs

Leak detection guide

How methods compare

Insurance claims

Escape of water explained

London-wide

Trace & Access across all 33 boroughs

Same multi-method kit and fixed-fee approach from Barking to Richmond. Pick your borough for local housing detail.

Water going somewhere it shouldn't?

Tell us the symptoms and your postcode. We'll confirm the visit, the fixed detection fee and the arrival window before you commit to anything.

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